U.S. Pat. No. 7,919,159 B2 to Liu et al. (“Liu”) discloses a composition of a polyester, a partially aromatic polyamide, a cobalt salt and an ionic compatibilizer that is a copolyester containing a metal sulfonate salt. Liu teaches that the use of a transition metal catalyst to promote oxygen scavenging in polyamide containers is well known. Liu further teaches that blends of an ionic compatibilizer (copolyester containing a metal sulfonate salt) and a cobalt salt results in a container having improved gas barrier properties, improved haze and reduced yellowness. Liu also teaches that blends of polyesters and polyamides suffer from issues of haze and yellowness.
U.S. Pat. No. 8,871,846 B2 to Fava (“Fava”) discloses a composition of a polyester, a polyamide, a transition metal catalyst and an inert organic compound selected from the group consisting of paraffins, vegetable oils, polyalkylene glycols, esters of polyols, alkoxylates, and mixtures of these substances with linseed oils being an example of such a vegetable oil. Fava discloses that the use of an inert organic compound, which preferably is liquid at ambient temperature, in transition metal-based polyester/polyamide compositions for the forming of articles, e.g. packaging materials for personal care, medical pharmaceutical, household, industrial, food and beverage plastic products, shows a considerable improvement of the oxygen scavenging performance and a considerable reduction or a complete elimination of the oxygen scavenging induction period compared with known transition metal-based polyester/polyamide blends not comprising an inert liquid organic compound.